#include <iostream>
using namespace std;

class Fish{
    protected:
        bool isSwimWaterFish;
    public:
        Fish(bool isSwimWaterFishFlag):isSwimWaterFish(isSwimWaterFishFlag){

        }
        void Swim(){
            if (isSwimWaterFish){
                cout<<"swim is lake"<<endl;
            }else{
                cout<<"swim is sea"<<endl;
            }
        }
};

class Tuna:public Fish{
    public:
        Tuna():Fish(true){

        }
        void Swim(){
            cout<<"swim very slow"<<endl;
        }
};


class Carp:public Fish{
    public:
        Carp():Fish(false){
            
        }
        void Swim(){
            cout<<"swim very fast"<<endl;
            Fish::Swim();
        }
};


int main(){
    Tuna tuna;
    tuna.Swim();
    Carp carp;
    carp.Swim();
    carp.Fish::Swim();
    return 0;
}
